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Laurent Duval
Laurent Duval
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In one of the homeworks that I am dealing with for Linear Systems course, I have encountered with such a statement: Consider $C^N$$\mathbb{C}^N$ the vector space of N dimensional complex vectors. We can define a basis F={f1,...,fN}$F=\{f_1,\ldots,f_N\}$ where \begin{align} f_k = \begin{bmatrix} f_{k,1} \\ f_{k,2} \\ .\\ .\\ f_{k,N} \end{bmatrix} \end{align}

and $f_{k,l} = \frac{1}{N}e^{\frac{j2\pi(k-1)(l-1)}{N}}$. It is straightforward to show that those vectors are orthogonal, but I have no idea about how to show that those vectors are linearly independent, and their span is $C^N$$\mathbb{C}^N$. Could you please give me a clue?

In one of the homeworks that I am dealing with for Linear Systems course, I have encountered with such a statement: Consider $C^N$ the vector space of N dimensional complex vectors. We can define a basis F={f1,...,fN} where \begin{align} f_k = \begin{bmatrix} f_{k,1} \\ f_{k,2} \\ .\\ .\\ f_{k,N} \end{bmatrix} \end{align}

and $f_{k,l} = \frac{1}{N}e^{\frac{j2\pi(k-1)(l-1)}{N}}$. It is straightforward to show that those vectors are orthogonal, but I have no idea about how to show that those vectors are linearly independent, and their span is $C^N$. Could you please give me a clue?

In one of the homeworks that I am dealing with for Linear Systems course, I have encountered with such a statement: Consider $\mathbb{C}^N$ the vector space of N dimensional complex vectors. We can define a basis $F=\{f_1,\ldots,f_N\}$ where \begin{align} f_k = \begin{bmatrix} f_{k,1} \\ f_{k,2} \\ .\\ .\\ f_{k,N} \end{bmatrix} \end{align}

and $f_{k,l} = \frac{1}{N}e^{\frac{j2\pi(k-1)(l-1)}{N}}$. It is straightforward to show that those vectors are orthogonal, but I have no idea about how to show that those vectors are linearly independent, and their span is $\mathbb{C}^N$. Could you please give me a clue?

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Canberk
Canberk
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DFT as an Orthogonal Basis Change

In one of the homeworks that I am dealing with for Linear Systems course, I have encountered with such a statement: Consider $C^N$ the vector space of N dimensional complex vectors. We can define a basis F={f1,...,fN} where \begin{align} f_k = \begin{bmatrix} f_{k,1} \\ f_{k,2} \\ .\\ .\\ f_{k,N} \end{bmatrix} \end{align}

and $f_{k,l} = \frac{1}{N}e^{\frac{j2\pi(k-1)(l-1)}{N}}$. It is straightforward to show that those vectors are orthogonal, but I have no idea about how to show that those vectors are linearly independent, and their span is $C^N$. Could you please give me a clue?